Since the release of the 3rd Generation Partnership Project Release 7 (3GPP Release 7), policy and charging function is achieved by Policy and Charging Control (PCC) frame. PCC architecture is a functional frame that can be applied to multiple access technologies, for example, PCC architecture can be applied to Terrestrial Radio Access Network (UTRAN) of Universal Mobile Telecommunications System (UMTS), Global system for Mobile Communication (GSM)/Enhanced Data Rate for GSM Evolution (EDGE) radio access network, Interworking-Wireless Local Area Network (I-WLAN) and Evolved Packet System (EPS).
PCC mainly achieves two functions of policy control and charging. FIG. 1 is a schematic diagram of the architecture of existing PCC, and each logic functional entity in the PCC architecture as shown in FIG. 1 and the interface functions thereof are described below. As shown in FIG. 1,
Application Function (AF) is used to provide an access point for the service applications, and the network resources used by these service applications require a dynamic policy control. When performing a parameter negotiation on a service panel, AF transmits related service information to a Policy and Charging Rules Function (PCRF) entity. If the service information accords with the policy of the PCRF, the PCRF accepts the negotiation; otherwise, the PCRF refuses the negotiation and gives service parameters that are acceptable by the PCRF in the feedback. Then, the AF may return these parameters to a User Equipment (UE). Wherein the interface between the AF and the PCRF is a Rx interface.
PCRF, which is the core of PCC, is responsible for making policy and charging rule. The PCRF provides network control rules based on service data flows, these network controls include: the detection of the service data flow, Gating Control, Quality of Service (QoS) control and charging rules based on data flows. The PCRF transmits the made policy and charging rules to a Policy and Control Enforcement Function (PCEF) entity to be implemented; meanwhile, the PCRF is also required to guarantee that theses rules are in accordance with the subscription information of the user. Wherein the policy and charging rules made by the PCRF comprise: service-related information obtained from the AF; user policy and charging control subscription information related to the policy control and charging obtained from a Subscription Profile Repository (SPR); information related to a bearer network obtained from the PCEF via a Gx interface.
The PCEF generally locates within a Gateway (GW), and implements the policy and charging rules made by the PCRF on a bearing panel. The PCEF detects service data flows according to a service data flow filter contained in the rule transmitted from the PCRF, so as to perform the policy and charging rules made by the RCRF on the service data flows; when establishing a bearer, the PCEF allocates resources according to the rules transmitted by the PCRF, and performs gating control according to information provided by the AF; meanwhile, the PCEF triggers reporting of an event occurred on the bearer network according to the events subscribed by the PCRF; according to the charging rules transmitted from the PCRF, PCEF performs charging operation for corresponding service data flows, wherein the charging may be online or offline. In the case of an online charging, it is necessary that the PCEF performs a credit management together with an Online Charging System (OCS); and in the case of an offline charging, the PCEF exchanges related charging information with an Offline Charging System (OFCS). Wherein the interface between the PCEF and the PCRF is a Gx interface, and the interface between the PCEF and the OCS is a Gy interface, and the interface between the PCEF and the OFCS is a Gz interface. The PCEF generally locates on the gateway of a network, for example, Packet Data Network-Gate Way (PDN-GW) of EPS, Gateway GPRS Support Node (GGSN) of General Packet Radio Service (GPRS) and Packet Data Gateway (PDG) of Interworking WLAN (I-WLAN).
Bearer Binding and Event Reporting Function (BBERF) entity generally locates within an access network gateway. For instance, if a user equipment accesses an EPS via an E-UTRAN and Proxy Mobile Internet Protocol version 6 (PMIPv6) is employed between the S-GW and the P-GW, then the BBERF exists in the S-GW. If a user equipment accesses via a creditable non-3GPP access network, then the BBERF also exists in the creditable non-3GPP access gateway.
The Subscription Profile Repository (SPR) stores user policy charging control subscription information related to the policy control and charging. The interface between the SPR and the PCRF is a Sp interface.
The OCS and the PCEF jointly complete the control and management of the user credit in the case of online charging.
The OFCS and the PCEF jointly complete the charging operation in the case of offline charging.
In the prior art, PCC supports dynamic usage monitoring control for performing a dynamic policy decision based on a total amount of the network resource usage in real-time. Usage monitoring can be applied to a single service data flow, a group of service data flows or all of the service flows of an IP-Connectivity Access Network (IP-CAN) session. Presently, usage refers to the data service of user panel. In the prior art, an instance required to be usage monitored is identified by a Monitoring Key, for example: if the PCRF allocates a Monitoring Key and corresponding threshold for all of the service flows of an IP-CAN session, then the PCEF monitors the traffic of all the service flows of the IP-CAN according to the threshold and identifies a reported usage with the Monitoring Key. If the PCRF allocates a monitoring key and corresponding threshold for one service data flow or a group of service flows, then the PCRF carries the Monitoring Key in a PCC rule corresponding to the service data flow or the group of service data flows, and monitors the traffic of the service data flows corresponding to the PCC rules having the same Monitoring Key, and identifies a reported usage with the Monitoring Key.
Meanwhile, a total allowanced usage of a certain PDN of a user may also be stored in an SPR, i.e. a total allowanced usage for all of the service flows of one IP-CAN session, which may also be referred to as a total allowanced usage per PDN per user. SPR may also stores a total allowanced usage for certain specific services of a PDN of a user, i.e. the total allowanced usage for one service data flow or a group of service data flows, which can also be identified with the Monitoring Key.
After the user establishes an IP-CAN session to a certain PDN, the SPR distributes the total allowanced usage to the PCRF. When PCRF performs a usage monitoring control, the PCRF subscribes a Usage_Report event trigger from the PCEF. After the Monitoring Key contained in the PCC rule is distributed, PCC rules having the same Monitoring Key share a threshold corresponding to the Monitoring Key. When the Monitoring Key is not contained in any PCC rule, all of the service data flows of the IP-CAN session share a threshold corresponding to the Monitoring Key. When it is monitored by PCEF that the usage reaches a threshold, an IP-CAN session terminates, all of the PCC rules containing a certain Monitoring Key are deleted or the PCRF explicitly requests a usage report, PCEF will reports the usage consumption of a related monitoring key since the last report to the PCRF. After the PCRF receives the usage report from the PCEF, the PCRF deducts the reported usage from the total allowanced usage. If the PCEF reports the usage of a certain monitoring key and a further monitoring is required, the PCRF will allocate a new threshold to the PCEF; and if no further monitoring is required, the PCRF will not allocates a new threshold to the PCEF. After the last IP-CAN session of an APN of the user terminates, the PCRF stores, in the SPR, the remaining allowanced usage comprising the total allowanced usage of the PDN or the total allowanced usage of some specific services of the PDN.
It can be seen from existing usage monitoring control scheme that existing usage monitoring control is performed for a certain PDN of a user or certain specific service flows of a certain PDN. Having some limitations, existing usage monitoring control cannot be applied in some cases, for example: for a family package, multiple users participated in this family package share a a total allowanced usage of a certain PDN or a total subscription allowanced usage of certain specific service flows of a certain PDN. In this case, the PCRF should simultaneously perform a usage monitoring on multiple IP-CAN sessions to the same PDN established for multiple users participated in this family package or certain specific service flows to the same PDN.
In the prior art, when multiple users share a total allowanced usage, there is provided no solution that a PCRF simultaneously performs usage monitoring on multiple users according to a total allowanced usage. If still using existing usage monitoring control method for implementing a monitoring control on the user equipments sharing the same subscription information, then it will definitely lead to conflicts in policy and charging controls.